Fluid deflector for well drills



Oct. 28, 1941. sco-r'r 2,250,487

FLUID DEFLECTOR FOR' WELL DRILLS Filed Feb. 27, 1940 9- loya L.$c0 I? INVENTOR.

' W ,bZZ- ATTORNEYS.

Patented Oct. 28,

2,260,487 FLUID narmzo'ron FOR WELL DRlLLS J Floyd L. Scott, Houston, Tex., assignor toflughes Tool Company, Houston, Tex., a corporation of Delaware Application February 27, 1940, Serial No. 320,985

e 3 Claims.

My invention relates to well drills and more particularly to means upon such drills for directing the course of the flushing fluid relative to the cutters.

In well drills the flushing fluid, employed in clearing the cutters of the cuttings and carrying said cuttings to the surface, is normally filled with abrasive particles, sand and the like. This fluid circulates at high speed and under high pressure and the sand tends to cut the metal of the bit. Hard metal is employed in the fluid discharging nozzles and in the cutters to resist this wear. However, the flushing fluid isdeflected laterally upon contact with the cutters and is forced in around the bearings of the cutters so strongly that undue wear upon the bearings is experienced. The bearings are found to be cut away by the flushing fluid so that their normal life is materially shortened. The bearings normally are subjected to heavy wear due to the weight of the drilling string upon thebit and the rotation of the drill, but'due to the strong circulation of mud about the bearings, further wear results and the bearings and interior of the cutters do not last during the life of the teeth upon the cutters.

It is an object of theinvention to provide a deflecting means upon the drill which will be engaged by the stream of flushing fluid and direct the said fluid away from the bearings.

I aim to form adjacent the base of a rotating cutter, a battle which directs the flushing fluid laterally toward the bit head, and away from the cutter bearings and still efficiently cleans, the teeth of the cutter. The invention also includes a deflecting recess in the body of the drill.

In the drawing herewith Fig. 1 is a central longitudinal section through one section' ofa three cone bit embodying the normal type of bit and illustrating the course of the flushing fluid where my deflecting recess is employed. i

Fig. 2 is a perspective view of the cutter shaft and adjacent portion of the bit head with my deflecting plate and recess both employed thereon.

Fig. 3 is a broken sectional detail showing the manner in which the flushing fluid is diverted away from the cutter bearings.

The drill to which my invention is applied in the drawing is a well known type of drill in which the head is formed in three longitudinal sections, each equipped with a cutter shaft and a conical shaped cutter thereon. In Fig. 1, one such section is shown. The body portion I, has an upwardly tapered and threaded shank 2 and the lower end is inclined downwardly and outwardly on its inner face 3. Upon this face "is a down- I .wardly inclined cutter shaft 4.

Three such sections are fitted and welded together for connection to a drill collar for drilling.

The cutter shaft has raceways 5 and 6 formed therein to receive the rollers 1 and balls 8 respectively. ,At the end of the shaft is a recess into which is pressed a hard metal pilot pin 9. An approximately conical shaped cutter I0 is fitted over the endof the shaft. It has raceways to receive the hearings in the usual manner. Surrounding the pilot pin 9 in the cutter is a hard bearing ring or bushing ll. After the cutter has been placed upon the'shaft the balls 8 are inserted into position 'in the raceways 6, through a bore l2 which is then filled with a plug l3 which is then locked against removal by welding material. a

The cutter is formed with circumferential rows of cutting teeth l4 thereon in a manner well known in the art. The cutter wall ha a fluid circulating opening l5 therein and it will be understood that the flushing fluid will fill the spaces on the interior of the cutter about the bearings so as to reduce friction and keep the bearings cool.

The flushing fluid is discharged against the surface of each cutter adjacent the base thereof through a discharge nozzle l6. As shownin Fig. 1

the fluid engages the cone surface and is deflected laterally, part of the stream being directed only a small amount of the mud will flow down about the base of the cone and around the bearings. The larger portion will enter the recess I 8 in the bit head and be deflected back. The portion of. the'stream that circulates into the space about the base of the cutter is insufficient to cause excessive wear upon the bearings suchas would otherwise result from the splashing of the fluid in the direction of the shaft.

To further alleviate this wear upon the bear-v ings, I may place a baflle or deflector plate l9 upon the inner face 3 of the bit head and about This plate may be in the form of a flange formed integral with the head as shown in Fig. 3 or it may be welded in place after the head is formed as will be obvious from Fig. 2.

This plate I!) The lateral stream will bediverted by the flange or plate into the recess l8 to be engaged by the flushing fluid discharged by said nozzle to direct the course of said fluid away and from thence back toward the axis of the drill. The flange when separately formed may a be of a hard wear resisting material which will endure during the life of the cutting surface" of I combination of a deflector plate on said head about the upper portion of each of said cutters from thebearings of said cutters.

2. In a well drill having a head, a cutter shaft thereon, a cutter rotatable onbearings on said shaft and a nozzle to discharge flushing fluid upon said cutter, the combination of a recessed and curved outwardly inclined surface thereon, a cutter shaft 4 projecting from said surface, a cutter rotatable thereon, cutters on said shafts and a nozzle to U discharge flushing fluid upon said cutters; the

on said shaft, a fluid discharge nozzle to deliver flushing fluid upon said cutter, an arcuate flange formed on said surface conforming to the 'outer curvature of said cutter, said flange acting to divertflushin'g fluid away from said shaft.

' FLOYD -L. SCOTT. 

